Sometime late this afternoon a political tremor in Italy might be felt in Europe's capitals.

It is not certain. Little is in these Italian elections, but it might happen and is worth tuning in for.

Beppe Grillo has been one of the stories of this Italian election. He is a comedian who has filled the piazzas across Italy. He does not deliver speeches. He rants and rages against the political class in Italy and the elites in Europe.

He has been denounced as a populist and a demagogue. The established politicians have attacked him as a threat to democracy. The leader of the centre-left, Pier Luigi Bersani, said that Mr Grillo risked taking Italy down the same road as Greece.

Mr Grillo can be funny and foul-mouthed. He is loose with his facts. He welcomes the foreign media and bars access to Italian journalists who he regards as tainted by the system.

He is scathing about Italy's politicians who he condemns as corrupt. He is a man set on tearing down but offers little idea as to what he would put in its place.

Yet he has built a protest movement which demands nothing less than a political revolution in Italy.

He may win 20% of the vote, perhaps even more. If he achieves that it will have been done without giving any Italian TV interviews. His is an internet-based campaign. He draws momentum from the crowds and the streets.

If he polls higher than 20% this comedian could become a player, a broker in determining Italy's next government. He himself will not be in parliament.

He is barred from standing, having been convicted of manslaughter for a car accident. So the next parliament may have 70 or 80 inexperienced MPs without the guidance of the man who has built this movement.

Mr Grillo could well have a say over Italy's future. He may demand electoral reform as the price of supporting any coalition government.

Europe's leaders will be watching anxiously in case Italy sends a powerful message to the rest of the continent of anger and despair over recession, corruption and the high price being paid to save the single currency.